Insulator



June 23,1931. (3, EARHART 1,810,950

I1\"SULATOR Filed April 5 1930 Patented June 23, 1931 PATENT OFFICEALBERT C. EARHABT, OI CLEVELAND HEIGHTS, OHIO msummon Application filedApril 5,

This invention relates to an insulator adapted for use in connectionwith telephone lines or low tension transmission lines. An object of theinvention is to provide qsuch an insulator in which the insulating.

' material used shall be rubber. A further object is to provide aninsulator which ma be manufactured very cheaply and whic willnevertheless be well adapted for its in- 1 tended) purpose. A furtherobject is to provide an insulator composed of several "parts in whichthe parts may be readily and conveniently assembled. Other and morespecific objects will appear from the descrip- ,tion and drawin s.

Fig. 1 is a sectional view showing my im proved insulator in position ona cross arm; Fig. 2 is a similar View at right angles to the view inFig. 1 and showing most of the parts 20 in elevation; Fig. 3 is a planview; Fig. 4 is a sectional view of the insulating. member removed fromthe assembly and corresponding substantially to the showing thereof inFig. 1; Fig. 5 is an elevation of the parts shown 25 in Fig. 4; Fig. 6is a detail plan view of the ring member; Fig. 7 is a detail elevationof a strap member and Fig. 8 is a detail in perspective of thecap'member. 3

In the drawings I have represented a frag- 80 ment 10 of a conventionalcross arm to which my insulator is adapted to be attached. A bolt 11which may have a nut threaded thereon or which may be a wood screw isemployed for securing the upright or supporting member 12 to the crossarm. The member 12 comprises a metal stamping formed with a cylindricalshank portion 13 having the edges abutting and an enlarged end 14 alsohaving abutting edges. The lower portion of member 12 is enlarged toform an attaching end portion having one open side, the edges 15 and 16being separated to about the width of the enlarged attaching end portionof the member 12. The metal at the lower end of the member 12 is turnedin to form a flange 17 which is open at one edge and which may extendbetween the cross arm 10 and a head of the bolt 11 whereby said boltfirmly 50 clamps the member 12 to the cross arm. It

1930. Serial No. 441,773.

will of course be understood that a difl'erent type of upright orsupporting member may be employed, for example, a solid bar having anenlarged upper end and a shoulder adapted to engage the cross arm 10,but I prefer the type shown since it can be produced very cheaply and isin all respects admirably. suited to its purpose.

Adapted to be slipped over the enlarged upper end 14 of the supportingmember 12 is a rubber insulating member having a body portion 18provided with a cavity adapted to receive the supporting member andhaving a groove 19 adapted to receive aconductor 20 such as a telephonewire. The cavity already mentioned comprises an enlarged portion 21adapted to receive the enlarged head 14 and a restricted neck portion 22adapted to snugly receive the shank 13 together with a flaring skirtforming cavity portion 23 which will provide an interruption for acoating of ice or water which might form over the insulator when-it isexposed to the weather. The body portion is also provided with anintegral shoulder 24 and such shoulder has a shoulder skirt portion 25and a shoulder bearing 26 between the shoulder skirt 25 and the body 18.The shoulder has depressions 27 formed therein for the reception ofconductor attaching means. The shoulder depressions 27 may be narrowedabove the shoulder bearing and widened therebelow as shown in Fig. 2 orit may have a uniform width, as shown in Fig. 5. It will be understoodthat the relative sizes of the shank 13 and enlarged end 14 as well asthe corresponding enlarged cavity 21 and restricted neck portion 22 maybe difl'erent from those shown in the drawings and it is contemplatedthat the relative size will be selected suchthat the greatest ease ofinsertion may be attained consistent with resistance to any force whichmight be encountered tending to pull the insulator oii the support 12.

A cap 41 which may be of a semi-cylindrical shape as shown'in Fig. 8 andprovided with a complementary groove 31 is provided to cooperate withthe insulator 18 to receive the conductor 20 and insulate the insertedthrough said slots.

member comprises a flat portion,

same from metallic parts. This cap is provided with a plurality ofnotches 32 in the same face which engages the groove-containing face ofthe insulating member 18. A strap member 33 is provided having the yokeportion thereof conforming in shape to the cap and provided with legs 34adapted to be received in the notches 32 whereby the cap and strap maybe assembled as a unit at the time of manufacture and in order to secureconvenience and installation. The strap 33 is provided with legs 35extending from the portion 33 and having struck-out barbed tongues 36 atthe lower end thereof. These tongues may be resilient whereby they willspring outwardly after being inserted in the notches 37 or they may bebendable and bent to holding position after the strap has been A ringmember 38, best seen in Fig. 6, is provided to engage under the shoulderskirt 25 against the shoulder bearing 26 to cooperate with the strap 33in securing the cap 30 in conductor gripping position on the body 18.This rin a cylindrical flange 39 extending therefrom and projections 40at the ends thereof provided with the slots 37 adapted to receive thelegs 35 and be engaged by the barbed tongues 36 thereof to hold theentire insulator in assembled position. It will be noted that the legs35 extend along and in the depressions 27 of the body 18.

In assembling my improved insulator in position of use it is onlynecessary to attach the supporting member 12 to the cross arm 10 bymeans of bolt 11, slip the rubber insulating portion 18 over theenlarged end 14,

having previously placed the ring member 38 thereon, place the conductor20 in the groove 19, place the end cap and strap unit in position withthe lower ends of the legs 35 extending through the slots 37 to securethe parts in fixed relationship to each other.

From the foregoing it will be evident that I have provided a simple,convenient and cheap insulator which is well adapted for its intendedpurpose and while I have shown and described certain embodiments I wishit understood that I am not limited to the detailed structure shown butmay carry out my invention in numerous varying forms within the scope ofthe appended claims.

Having thus described my invention, what I claim is:

1. In an insulator, means adapted to have one end thereof attached to asupport, the other end thereof being enlarged, a rubber insulatingmember having a cavity formed therein, said cavity having a restrictedneck portion, said enlarged end being received in said cavity andyieldably held therein, and means associated with said insulating memberfor securing a conductor thereto.

2. In an insulator, means adapted to have one end thereof attached to asupport, the

other end thereof being enlarged, a rubber in said restricted neckportion.

3. In an insulator, means adapted to have one end thereof attached to asupport, the other end thereof being enlarged, a rubber insulatingmember having a cavity formed therein, said cavity having a restrictedneck portion, said enlarged end being received in said cavity andyieldably held therein, and "means associated with said insulatingmember for securing a conductor thereto,

said first-means comprising a sheet metal member including a shankportion and an g enlarged end portion having abutting edges and anenlarged attaching end portion having the edges separated and a bottomflange for engagement with a headed attaching means.

4. A rubber insulator-including a body portion having formed therein acavity, said cavity including an enlarged portion, a restricted neckportion communicating with said enlarged portion and a flaring skirtforming portion continuous with said neck portion, a conductor receivinggroove in the end opposite said skirt forming portion and extendingthereacross and an intermediate integral shoulder portion, said shoulderportion including a shoulder bearing adjacent the body of the insulator,pressions in said shoulders to receive porions of a conductor securingmeans.

5. An insulator including a rubber body portion, means for securing thesame to a support, a shoulder integral therewith, depressions in saidshoulders, a groove extending across one end of said body portion, aring encircling said body portion, bearing against said shoulder andhaving slotted projections extending through said depresslons, a capcooperating with said groove, and a strap passing over said cap andhaving legs extending along and received in said depressions, said strappassin through the slots in said projections an secured thereto.

6. An insulator including a body portion, means for securing the same toa support, a shoulder integral therewith, depressions in said shoulders,a groove extending across 1 one end of said body portion, a ringencircling said body portion, bearing against said shoulder and havingslotted projections extending through said depressions, a capcooperating with said groove, and a strap there being de-- passing oversaid cap and. having legs extending along and received in saiddepressions, said strap passing through the slots in said projectionsand secured thereto.

7. An insulator including a body portion, means for securing the same toa support, a shoulder integral therewith, depressions in said shoulders,a groove extending across one end of said body portion, a ringencircling said body portion, bearing against said shoulder and havingslotted projections extending through said depressions, a capcooperating with said groove, and a strap passing over said cap andhaving legs extending along and received in said depressions, said strappassing through the slots in said projections and secured thereto bymeans of a barb tongue.

8. An insulator including a body portion having a conductor-receivinggroove extending thereacross, a cap having a complementaryconductor-recelving groove in one face thereof and notches formed insaid face, a strap having a portion conforming to a portion of said capand lugs extending into said notches whereby said cap and strap may beassembled as a unit for convenience in assembling the completeinsulator, and means securing said strap to said body portion, therebeing a shoulder portion integral with said body portion, depressions insaid shoulders, a ring having projections thereon and slots in saidprojections, said straps having legs extending through said slots andsecured therein by barb tongues struck out of said legs.

In testimony whereof, I hereunto afiix my signature.

ALBERT C. EARHART.

